TandemGeek

Not that it's of any consolation or help to those of you running belts, I had a revealation over the weekend with regard to at least some of the timing chains that come on Co-Motion's tandems.... They're 8 speed!

We were out riding with friends on Sat & Sun and during Sunday's ride a new Periscope triplet blew a link off the rear-most timing chain. I figure no big deal, as I always carry at least one 9 speed master link in our seat pack.

So, I go to put the link on and it's not wide enough by about .25mm! Moveover, since the Periscope is a 10 speed and running a Shimano chain on the drive-side there's no way to cannibalize that chain for parts.

I forced the 9 speed master link onto the chain by rolling the chain back onto the timing rings such that chain tension pulled the master link into the closed position so they could finish the ride but wow, what an unwelcomed surprise that was.

I've since re-stocked my seat pack with 8, 9 and 10 speed masterlinks and also threw in three three-link 8, 9 and 10 speed chain segments so I'll be better prepared in the future. I really miss the old days when you could use a chain breaker to fix chains out on the road before Shimano introduced it's one-time use rivet pins and when you could be pretty sure that the drive side and timing chains were at least the same width, e.g., all 8 speed or all 9 speed. It was also nice when a master link and a craft-quality or imported beer cost about the same as it made for an easy pay-back; I'm gonna have to raise my road-side service parts fee to a Margarita going forward.

rmac

Yes, they are getting expensive to keep some in our various bike bags -- $7.00 apiece.

I thought in an pinch 10sp would fit fine on 9sp and 9sp would fit on 10sp and the only differece would be the outside plates. Guess I should check that. However, I'll eventually have 10sp chains on all our bikes when the current ones wear out.

DCwom

Oh geez something else I didn't think about, now you've got me wondering about the timing chain on our tandem. Is there an easy way to determine the size of the chain? Our drive chain is a 9 speed (I assume since we have a 9 speed cassette), but I guess that is no guarantee that the timing chain is.

TandemGeek

Most have markings with the brand and model numbers that can be deciphered into their size, e.g., SRAM PC-48 = 8 speed, Shimano HG 7701 = 9 speed, Campagnolo C10 = 10 speed and so-on.

You can also use a Venier caliper to measure the overall width of the link's outer plates and that will give you a pretty good indication, with the approximate widths equating to...
For some reason there's a chapter from Sutherland's handbook on line that you can download that will allow you to decipher just about any of the more current chains that have their brand / model markings:
https://www.sutherlandsbicycle.com/Chapter5.pdf

zzzwillzzz

9 speed master links seem to work ok on dura-ace 10 speed. that could be one less link to carry.

i couldn't find one half of my 10 speed link after cleaning the chain one morning and was going to miss my group training ride. i threw on a 9 speed and rode it for about a week til i bought another 10 speed link.

jnbrown

Is there a reason to use a 10 speed timing chain?
9 speed lasts longer and is cheaper to replace.

bikeriderdave

Which, I'm sure, is the rationale for using 8-speed timing chains. Cheap, available, and (in theory, at least) more durable.

Come to think of it, if anyone knows where to purchase NOS "Sedisport" 7-speed chains, please share. No special pin or link required and the darned things lasted forever... could be the perfect timing chain!

TandemGeek

They'll do on 10 speeds in a pinch, but can sometimes cause chain skip or get hung-up on a bike that's running Campy 10 speed with a C10 chain: I'm a Campy guy so I'm duty bound to carry a SuperLink IV (Blue Card) even though I run both C10 and Shimano 10 speed chains on our Campy 10 single bikes.

Hmmmmm. Nope, can't come up with a good reason or even a smart-ass response that's actually humorous. It all ties back to weight-weenism, vanity and simplicity underscored by having access to wholesale pricing or very deep pockets. After all, if you can get stuff at cost or don't fret about cost, the world is your oyster.

Absolutely... You can't get much more low-tech than a timing chain in terms of it's function; however, it must be durable and as we discovered yesterday, you need to prepare accordingly for road side repairs which was the point of bringing it up. Again, I had no idea they were using 8 speed chains as it's been a long time since I've encountered anyone with a broken timing chain on a post 9 speed road tandem.


P.S. for bikeriderdave....

Will Trek be re-introducing the T1000 / T2000 tandems in '10 or has last year's omission turned into a strategy decision to bail out of that market?

rmac

Or very good exchange rates. I bought a bunch of 7801 chains for a little over $65 for three last spring. Since then, chain prices seem to have gone up quite a bit. I can't find 9sp chains much lower than that now. With all 10sp, inventory control and maintaining repair parts are a bit easier.

TandemGeek

True dat!

You know, as we finished our ride and discussed our friend's chain problem yesterday the cost of chains became painfully obvious when we discussed the cost of John-Q-Public changing out all of the chains on their new triplet and... gasp, it was over $120.00 using just basic Shimano branded 9 speed chains and not all that much less sticking with an 8 speed sync chain configuration.

Finding 8 and 9 speed components is truly becoming a bit of a challenge and when you do it's not like they're on close-out.

sch

Chains seem to be forever, compared with brifters, der etc in availability for 8-9spd, even 5-6
speed chains hang on in the catalogs. Our Macchiatto has an 8 spd timer, going strong at
6200mi, where the 10spd drive chain is upto # 3. # 2 literally disintegrated 30 yds into a 12%
grade 2 weeks ago, exam showed the endplate fractured vertically across the pin hole. With a
chain tool we were able to reassemble the chain after discarding 1.5" and gingerly ride home
at 8-12mph. 8spd chains can be as little as $10-15 on sale. Recently scored some 10spd
Shimano chains for $20 from Cambria. Profit margin on the $50-70 10spd chains must be formidable
as the weights are within an 0z or less regardless of price, and apart from blingy stainless or Ti
chains, the metallurgy of standards chains does not seem to be a distinguishing factor in price or
longevity.

Of course this disallows claims of better shifting achieved by asymmetric plates
recently introduced, but the incremental price of this can't be more than a few
bucks (plus engineering and development).

zonatandem

Was nice when a chainpunch and spare link was all you needed to fix a break instead of some of the $uper-priced fancy links that cost as much as a whole darn chain used to cost.
Good old days? Mebbe . . .
Seems anything you need to buy now has an extra Zero attached . . . but remember: zero means "nuttin'!"